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How to allow button click events if window in the background

I have an application, ParentApp, which launches another application, ChildApp.
ParentApp displays a form while the ChildApp is running - just a kind of Childapp is currently running display with a Cancel button which kills ChildApp.
I want ParentApp to be unusable while ChildApp is running, so whenever someone clicks on ParentApp I want to bring the ChildApp to the foreground, which is fine.
So I've added this event handler to the ParentApp which responds to the Activated event of the form.
private void ParentAppForm_Activated(object sender, EventArgs e)
{
IntPtr childHwnd = _childApp.MainWindowHandle;
SetForegroundWindow(childHwnd );
}
(GotFocus didn't seem to work)
Unfortunately, if the user clicks the Cancel button on the ParentAppForm, the event handler for that button is never hit, because the Activated event fires first and sets the foreground window to another process.
Is there around this - to allow the button event to fire even though the application is not in the foreground?

As a quick workaround, you could check whether the mouse pointer in inside the area described by the Button.Bounds when the Form is activated.
You can translate the mouse pointer position to the Form.Bounds coordinates using PointToClient with the Cursor.Position coordinates.
Something like this:
private void ParentAppForm_Activated(object sender, EventArgs e)
{
if (this.button1.Bounds.Contains(this.PointToClient(Cursor.Position)))
ChildForm.Close(); //Or ChildApp.Kill()
else
ChildForm.BringToFront(); //Or SetForegroundWindow(ChildApp.Handle)
}

C# WinForms events not firing

As the title suggests, I cannot get a single event to fire from an MDIChild application. No mouse event, no load, keypress, nothing at all.
private void btnSave_Click(object sender, EventArgs e)
{Console.WriteLine("Clicked");}
this.btnSave.Click += new System.EventHandler(this.btnSave_Click);
Selected the event from the properties window, manually subscribed to the event and yet nothing at all.

As the comments suggest you could insert a break point to see if these events are being fired.
From the information in your question it looks like the issue is that you're calling
Console.WriteLine
From a Winforms application.If you want to see somethng appear you could try
MessageBox.Show("Clicked")
Console applications would show Console.WriteLine, but the fact that you have buttons suggests a WinForms app.

Slow reaction of MouseClick event for NotifyIcon

I noticed strange behaviour of left-click event for NotifyIcon.
I have a code like this:
private void notifyIcon2_MouseClick(object sender, MouseEventArgs e)
{
if (e.Button == System.Windows.Forms.MouseButtons.Left)
{
Console.WriteLine("Hello!");
}
}
The problem is that upon clicking notifyicon in tray string "Hello" is not shown immediately, it takes about 0.5 seconds (half of a second) to react. That is why I can not add some sort of variable-counter for each click of the icon - it just reacts too slow to catch all clicks and increment my variable.
Is there any solution to the problem? I tried MouseClick, MouseDown, MouseUp and Click events, and all of them have such a slow reaction.
Thank you!

I think it is related to this little comment they make here (I know this is not this NotifyIcon).
Note that the LeftClickCommand fires after a short delay (as opposite to the DoubleClickCommand that fires immediately). This is because there is a time span between a first click and a second click for the OS to consider the mouse action a double-click. The NotifyIcon is smart enough to wait this period in order to make sure the LeftClickCommand is only fired if the user does not click a second time within that period.
I tried it and this delay is present on the Form itself as well. This is just how this event works.

Implementing a handler for the DoubleClick event was not a solution in my case where I wanted only the single click to open the NotifyIcon's popup.
I found the NoLeftClickDelay property in the code completion that makes things to work as wanted.
TaskbarIcon tbIcon = (TaskbarIcon)FindResource("MyNotifyIcon");
tbIcon.NoLeftClickDelay = true;

C# How to make webbrowser clickable

I was wonder how can I fire an event when the user double click on my webbrowser component. Since it has no such event how it could be possible...
Thanks in advance

Sounds like a WPF matter :-)
There you would go with an Behaviour attached to the browser. See this link for more information about this approach if you can alter your application (dependends on what you have done yet).
If you can't apply this solution, just bind a event handler to the click event and count click per time with respect to the mouse movement since the last click and if both conditions are true (two clicks in 0.2 secs, mouse hasn't moved more than 2px, for example) execute your double click code. The events you should use are previewMOUSEdown or MOUSEdown, not KEYdown.

// Call this where you want to create the event (let's say on the form load for example).
webBrowser1.DoubleClick += new EventHandler(webBrowser1_DoubleClick);
// This happens when the event is fired (so when you double click on the webbrowser control).
void webBrowser1_DoubleClick(object sender, EventArgs e)
{
// Code
}
Try this.
I don't know why you can't set this event via the designer :(, but this should work.

WPF: Slider doesnt raise MouseLeftButtonDown or MouseLeftButtonUp

I tried this XAML:
<Slider Width="250" Height="25" Minimum="0" Maximum="1" MouseLeftButtonDown="slider_MouseLeftButtonDown" MouseLeftButtonUp="slider_MouseLeftButtonUp" />
And this C#:
private void slider_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
{
sliderMouseDown = true;
}
private void slider_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
sliderMouseDown = false;
}
The sliderMouseDown variable never changes because the MouseLeftButtonDown and MouseLeftButtonUp events are never raised. How can I get this code to work when a user has the left mouse button down on a slider to have a bool value set to true, and when the mouse is up, the bool is set to false?

Sliders swallow the MouseDown Events (similar to the button).
You can register for the PreviewMouseDown and PreviewMouseUp events which get fired before the slider has a chance to handle them.

Another way to do it (and possibly better depending on your scenario) is to register an event handler in procedural code like the following:
this.AddHandler
(
Slider.MouseLeftButtonDownEvent,
new MouseButtonEventHandler(slider_MouseLeftButtonDown),
true
);
Please note the true argument. It basically says that you want to receive that event even if it has been marked as handled. Unfortunately, hooking up an event handler like this can only be done from procedural code and not from xaml.
In other words, with this method, you can register an event handler for the normal event (which bubbles) instead of the preview event which tunnels (and therefore occur at different times).
See the Digging Deeper sidebar on page 70 of WPF Unleashed for more info.

Try using LostMouseCapture and GotMouseCapture.
private void sliderr_LostMouseCapture(object sender, MouseEventArgs e)
private void slider_GotMouseCapture(object sender, MouseEventArgs e)
GotMouseCapture fires when the user begins dragging the slider, and LostMouseCapture when he releases it.

I'd like to mention that the Slider doesn't quite swallow the entire MouseDown event. By clicking on a tick mark, you can get notified for the event. The Slider won't handle MouseDown events unless they come from the slider's... slider.
Basically if you decide to use the
AddHandler(Slider.MouseLeftButtonDownEvent, ..., true)
version with the ticks turned on, be sure that the event was handled previously. If you don't you'll end up with an edge case where you thought the slider was clicked, but it was really a tick. Registering for the Preview event is even worse - you'll pick up the event anywhere, even on the white-space between ticks.